Spring shackle



Jan. 1, 19290 W. 5. JAMES SPRING SHACKLE Original Filed March 18, 1927 7INVENTOR. ZQ zIJz'mn 5. $477265 BY .TEY

Patented Jan. 1, 1929.

UNITED STATES PATENT OFFICE.

WILLIAM S. JAMES, 013 SOUTH BEND, INDIANA, ASSIGNOR TO THE STUDEBAKERGOR- EORATIOIN, OF SOUTH BEND, INDIANA, A CORPORATION OF NEW JERSEY.

SPRING SHAGKLE.

original application filed March. 18, 1927, Serial No. 176,5'70. Dividedand this application filed November 11, 1927.

This invention relates to elastic or resilient connections, and is adivision of my ending application filedMarch 18, 1927, erial No.176,570. This invention relates particue larly to spring shackleconnections, and more particularly to that type in which the resilientqualities may be varied and adjusted, the principal object being toprovide an elastic or resilient connection with means for m varying theresilient characteristics thereof.

Another object is to provide an elastic or resilient spring shackleconnection, in which the resilient material thereof is confined within acloseds ace, with means for adjustably controlling t e volume of thespace whereby the density of resilient material confined therein may bevaried to best suit conditions in which the connection is used. 'theabove being among the objects of the present invention, the sameconsists of certain features of construction and combinations of partsto be hereinafter described with reference to the accompanying drawing,and then claimed, having the above and other objects in view.

Figure 1 is a fragmentary side view of an automobile side frame memberand co-operating spring showing a shackle connecting the same, theconnection between the spring and shackle links being of a resilientnature and shown in section.

Figure 2 is a sectional view of the connection between the shackle andspring eye, taken on the line 2-2 of Figure 1.

In resilient connections commonly employed between relatively movableparts such as spring shackles and the like, it has often been foundnecessary to change the resilient characteristics of the same in orderthat the most advantageous results may be obtained from the devices soconnected or from the resilient connection itself. In such connections,it is the usual practice to employ rubber as the resilient elementtherein, and when it becomes necessary to change the resilientcharacteristics of the connection, it has been the usual practice tochange the grade or composition of the rubber to obtain the desireddegree of resiliency. A single resilient connection may be adaptable foruse in a variet of difierent parts or objects and it will be evidentthat it is extremely dlflllC-lllt in such a case, to provide a grade ofrubber which will Serial No. 232,594.

it is this last characteristic which has probably. caused the generalbelief in regard to its compressibility. Many constructions have beenprovided where means were employed for drawing down or squeezing therubber together, but so far as I have been able to determine, in allsuch constructions, the rubber was not confined within-a restrictedspace but on the contrary, there were apertures or spaces through whichthe rubber might extrude, for which reason its resilient characteristicswere affected but slightly if any,

i when it was attempted to compress the same.

I have found that if in such connections the rubber is positioned in aclosed space without any openings or spaces through which the rubber mayextrude upon being compressed, if the volume of such space is decreasedthereby compressing the rubber, the resilient characteristics of therubber are materially changed, the density of the rubber being increasedupon compression and its limit of elasticity accordingly diminished. Ihave made use of this fact in connection with spring shackles whichemploy rubber as the resilient element. 7

In accordance with the present invention, I construct the connections insuch a manner that the resilient element or elements thereof areconfined within a closed space devoid of any openings or spaces throughwhich the rubber may have an op ortunity of extruding and I provide reay adjustable means for varying the area of such spaces whereby theresiliency of the rubber contained therein may be varied and theresilient characteristics of such connection may be readily adjusted andcontrolled to most suitably correspond to the use to which it is put.

Referring to the accompanying drawing, in which like numerals refer tolike parts lit? throughout the several views, I show the presentinvention incorporated in a motor vehicle spring shackle. As inconventional structures, the links 10 are provided for shackling the endof the frame side member 11 to the end or" the spring 12, but theconstruction as shown discloses certain novel features in the connectionbetween the link and the spring end, and between the link 10 and the endoi the frame member 11. As the construction at both ends of the link 10is substantially the same, only one end will be described, it being keptin mind that the other end is substantially identical.

l he usual shackle belt of conventional construction is replaced in theconstruction shown, by an outer shell 13 of a length commensurate withthe width of the spring 12., and non-rotatably embraced within the eye27 formed at the end of same. Positioned within the sleeve 13 andcoaxial therewith, is a smaller sleeve 1% provided with a sub stantialspace between its outer surface and the interior wall of the sleeve 13.The ends of the sleeve 14 project outwardly beyond the ends of thesleeve 13 and are non-rotatably received within the ends of the links10. The washers 15, preferably of the type possessing dry lubricatingqualities, are positioned between the ends of the sleeve 13 and the adjacent linlrs 10. Expansion washers 16 are socured in the circumferentialgrooves 25, within the ends of the sleeve 13 and have central openingstherein adapted to receive the sleeve is in sliding contact with theouter surface thereof.

The inner sleeve id is provided with a plurality or slotted opening" 1'?connecting its interior with the space between its outer surface and thesleeve 13 between the expansion washers 16 which serve to seal the endsof the sleeve 13. Gne end of the sleeve 14 is provided with an expansionplug 18 seated in a groove 26, which seals that end, the other end beingprovided with an adjustable plug 19 threaded into that end of thesleeve. The interior of the sleeve 14 and the space between this sleeveand the sleeve 13 between the expansion washers 16 together with theopenings 1'2, are completely filled with rubber 21 or material havingsimilar characteristics which is preferably vulcanized or otherwisebonded to the contacting surfaces.

In this construction, it will be apparent that there is no rubbingaction of the parts connecting the shackle linl: 10 to the end of thespring 12 as is the case in conventional construction where a plainshackle bolt is used, instead in this construction upon movement of thespring 12, the rubber between the inner sleeve 14 and the outer sleeve13 is distorted to permit this movement and consequently there is nomoving contact between the parts and no friction surfaces to requirelubrication. in this type or shackle construction as aeeaoce in anyother type-of resilient connection, one application of the same mayrequire different resilient characteristics of the rubber. For instance,a vehicle adapted to carrying a heavy load and equipped with stitl'springs would require a rubber mounting of less resiliency than oneadapted to lighter loads. lhe resilient characteristic of the rubbermust be ad j usted to such a degree as will best adapt it to resist andcushion-the torque to which it is subjected.

The construction shown p :vides means whereby the resiliency of th'rubber may be varied or adjusted to best conform with the needs of eachindividual connection. This is accomplished by threading the plug 19either inwardly into the sleeve 14 to diminish the resiliency ot' therubber, or outwardly to in crease it. For instance, should lessresiliency of the rubber be required, the plug 19 may be threadedfurther into the sleeve 14 in which case the rubber will be forced aheadof the plug 19 and will be compressed, sutlicieut rubher passing throughthe openings 17 in the sleeve 14 to cause a likev compression in thespace between the inner sleeve 14 and the outer sleeve 13. The openings17 allowing means for equalization of the degree of compression on bothsides of the walls of the sleeve 14. Similarly greater resiliency of therubber may be obtained by backing the plug 19 further out of the sleeve14 and thereby allowing greater room for expansion, and making theresilient material more easily distortable.

From the foregoing description, it will be readily-apparent that thepresent invention provides ready and easy means for varying theresilient characteristics of resilient connections employing rubber orsimilar material as the elastic element and so permit such points to bereadily adaptable to the particular construction in which they areemployed. The present invention is easily adaptable to practically allconventional forms of resilient connections and in addition provides aconnection which is simple in structure, economical to manufacture andhighly efficient in use.

Formal changes may be made in the specific embodiment of the inventiondescribed without departing from the spirit or substance of the broadinvention, the scope Of which is commensurate with the appended claims.

What I claim is:

1. In a spring shackle, a pair of spaced concentric sleeves movablerelative to each other, closures for the ends of said sleeves, aperturesin the inner of said sleeves connecting the interior thereo] with theinterior of the outer of said sleeves, and a resilient material fillingthe connected interiors of said sleeves to allow movement of one of saidsleeves relative to the other of said sleeves.

2. In a spring shackle, a pair of spaced concentric sleeves movablerelative to each other, closures for the ends of said sleeves, aperilltures in the inner of said sleeves connecting the interior thereof withthe interior of the outer of said sleeves, a resilient material fillingthe connected interiors of said sleeves, and means for varying thevolume of said resilient material whereby the resilient character isticsthereof are changed.

3. In a spring shackle, a pair of spaced concentric sleeves movablerelative to each other, closures for the ends of said sleeves. aperturesin the wall of the inner of said sleeves connecting the interior thereofwith the interior of the outer of said sleeves, a resilient materialfilling the connected interiors of said sleeves to allow movement of oneof said sleeves relative to the otherthereof, one of said closures forthe inner of said sleeves being movable longitudinally thereof to varythe volume of said resilient material filling said connected interiorsto change the. resilient characteristics thereof.

4. In a spring shackle, a pair of spaced concentric sleeves movablerelative to each other, rigid closures for the ends of the outer of saidsleeves, a rigid closure for one end of the inner of said sleeves,openings formed in the wall of said inner sleeve connecting the interiorthereof with the interior of said outer sleeve, resilient materialfilling said connected interiors, and screw means threaded into the openend of said inner sleeve for varying the volume of said resilientmaterial to ch an go the resilient characteristics thereof.

5. In a shackle construction, a pair of concentric sleeves freely spacedfrom each other, one of said sleeves being positioned within the otherof said sleeves, rigid closures for the open ends of the outer of saidsleeves, a rigid closure for one end of the inner of said sleeves,openings connecting the interior of the inner sleeve with the spacebetween the same and said outer sleeve, a rubber filling for theinterior of both of said sleeves, and an adjustable plug in the open endof said inner sleeve for varying the combined volume of rubber enclosedby both of said sleeves.

6. In a motor vehicle, a frame side rail, a

spring having an eye formed at one end thereof, and a shackle forconnecting said spring with said side member, said shackle comprising anouter sleeve non-rotatably received in said spring eye, an inner sleevespaced concentrieally within said outer sleeve, shackle link secured tothe ends of said inner sleeve, rigid closures for the ends of said outersleeve, a rigid closure for one end of said inner sleeve,.openings inthe wall of said inner sleeve connecting the interior thereof with theinterior of said outer sleeve, resilient material filling said connectedinteriors, and a plug threaded into the open end of said inner sleevefor varying the volume of said resilient material to change theresilient characteristics thereof.

7. In a motor vehicle, a frame side rail, a leaf spring having an eyeformed at one end thereof, and a shackle for connecting said spring withsaid side member, said shackle comprising an outer sleeve non-rotatablyreceived in said spring eye having inner circumferential groovesadjacent its ends, an inner sleeve spaced concentrically within saidouter sleeve provided with an inner circumferential groove adjacent oneend thereof, shackle links secured to the ends of said inner sleeve,annular expandable washers surrounding said inner sleeve seated in. saidgrooves formed in said outer sleeve to close the ends thereof, a washerseated in said groove formed in said inner sleeve to close one endthereof, apertures in said inner sleeve connecting the interiors of saidsleeves, rubber filling for said connected interiors to resilientlyallow movement of one sleeve relative to the other, and a screw plugthreaded into the open end of said inner sleeve, whereby said plug maybe moved longitudinally of said inner sleeve for varying the volume ofsaid rubber to change the resilient characteristics thereof.

Signed by me at South Bend, Indiana, this 8th day of November, 1927.

WILLIAM S. JAMES.

